2007 Volume 47 Issue 5 Pages 715-722
Nine types of reinforcing steels having different Cr contents were placed in mortar simulating environments involving chloride attack, carbonation, and combined deterioration and subjected to corrosion-accelerating test for fundamental research on the corrosion resistance of Cr-bearing rebars in corrosive environments where reinforced concrete structures are to be constructed. The polarization resistance and corrosion potential of Cr-bearing rebars were then measured at temperatures of 60, 40, and 20°C to investigate their electrochemical properties in corrosive environments. Their corrosion area and average corrosion rate at the end of 40 cycles of corrosion-accelerating testing were also calculated to investigate their corrosion resistance.
As a result, the corrosion resistance of Cr-bearing rebars was found to increase as their Cr content increases in all corrosive environments, and the excellent corrosion resistance of Cr-bearing rebars with Cr contents of 5% or more and 7% or more was confirmed in uncarbonated and carbonated environments, respectively, with a chloride ion content of 1.2 kg/m3.